1 / 23

Recent LTL Excursions ?? Extraordinary...?? W. Walker TOC Workgroup August 18, 2009

Recent LTL Excursions ?? Extraordinary...?? W. Walker TOC Workgroup August 18, 2009.

tod
Télécharger la présentation

Recent LTL Excursions ?? Extraordinary...?? W. Walker TOC Workgroup August 18, 2009

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Recent LTL Excursions?? Extraordinary...?? W. WalkerTOC Workgroup August 18, 2009 . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage

  2. ? ?“..substantial evidence that exceedance is due to error or extraordinary natural phenomena…” ? ? . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage

  3. August 2008 & September 2009 Sampling Events • Refuge hydrologic variables within range of data from previous sampling events (rainfall, stage, stage increase, flow, TP load) on a 30-day & 7-day basis • Inflows & hydraulic gradients within ranges observed in previous excursions • Antecedent hydrologic conditions of limited use for evaluating causal relationships because of the complexity and long time scales associated with loading, storage, recycling, and transport of P in the marsh. . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage

  4. ~ Nov 2008 Excursion ~ June 2009 Excursion Restoration time scale following reduction in external load ~3 years for P stored in water column & vegetation; Longer if P is recycled from soils WWW TOC Presentation, Nov 2004

  5. Interior Marsh Water Quality, Stage, & Rainfall Sites

  6. 7-Day Rainfall & Daily Stage, 2006-2009 June 2009 Nov 2008 Marsh = Sites 7 & 9 Rim = 1-8C, S362, G300, G301, G338, G310, G251

  7. 7-Day Inflow Volume & Daily Stage, 2006-2009 June 2009 Nov 2008 Marsh = Sites 7 & 9 Rim = 1-8C, S362, G300, G301, G338, G310, G251

  8. 7-Day Inflow TP Load & Daily Stage, 2006-2009 Load June 2009 Nov 2008 Marsh = Sites 7 & 9 Rim = 1-8C, S362, G300, G301, G338, G310, G251

  9. Refuge Topography E.A. Meselhe (2009) based on USGS topography data. Elevations in feet, NGVD29. . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage

  10. Hydraulic Gradients Between Rim Canal & Marsh SitesMay 2006- June 2009 Units: feet. Rim = Average of 1-8C, S362, G300, G301, G338, G310, G251

  11. Antecedent Conditions for Each Sampling Event1978-1983 & 1999-200930-Day Rainfall (Inches) S5A+S6+S139 June 2009 1978-1983 Nov 2008

  12. 30-Day Antecedent Conditions for Each Sampling Event, 1978-1983 & 1999-2009Rainfall, Inflow Volume, TP Load, TP Conc, Marsh & Rim Stage, Increase in Marsh & Rim Stage Nov 2008 1978 - 1983 June 2009

  13. 7-Day Antecedent Conditions for Each Sampling Event, 1978-1983 & 1999-2009Rainfall, Inflow Volume, TP Load, TP Conc, Marsh & Rim Stage, Increase in Marsh & Rim Stage 1978 - 1983 Nov 2008 June 2009

  14. 30-Day Increase in Stage vs. Rainfall Greater risk of Marsh TP > LTL following heavy rainfall & rising stage in periods with positive net inflow vs. periods with net outflow. . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage Marsh Stage = Sites 7 & 9, Rainfall = Mean ( S5 + S6 + S39 ); Monthly Sampling Events, 1999-2009

  15. Long-Term Perspective • Given long time scales of P storage & recycling, causal factors & progress are best evaluated by tracking long-term trends in the marsh following long-term reductions in external loads. • Indications of long-term improvement in marsh conditions: • Decreasing frequency of marsh GM > LTL. • Decreasing trends in TP concentrations at some sites • Effects of reduced loading confounded with drought • Indications that CD objectives have not yet been achieved: • Exceedance of LTLs for Interior Marsh • Interior GM > long-term objective (7 ppb) in each Water Year (2000-2009). • Exterior Marsh not restored . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage

  16. Trends in Rainfall & Refuge Inflows, WY 1996-2009 . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage

  17. 10-Year Trend in Marsh Geometric Mean TP vs. Consent Decree Goal ( < 7 ppb ) Consistent with Achieving Long-Term Levels

  18. Trends in Marsh Total P & Conductivity, WY 2000-2009 . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage

  19. Monthly Flows & TP Concentrations – STA 1E Inflows & OutflowsMay 2001 – June 2009 Inflow Inflows Outflow . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage

  20. Monthly Flows & TP Concentrations – STA 1W Inflows & OutflowsMay 2001 – June 2009 Inflows Outflows . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage

  21. Trends in Yearly Flow and TP Concentration at S5A Pump Station & Inflow to STA1W Design Assumption for STA1W Inflow TP Conc, EAA Regional Feasibility Study ~ 160 ppb . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage WY 2010 data for May-June Only

  22. 12-Month Rolling STA 1W Inflow TP Loadvs. Existing Operational Envelope April 2000 – June 2009 Deja Vous? 36-Year Maximum Mean . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage

  23. Recommendations • Continue tracking compliance & trends in marsh • Focus on load reduction measures • Recent increases in STA outflow concentrations may cause reversal of favorable marsh trends: • Overloading of both STA’s relative to existing & future operational envelopes • Problems with depths & vegetation in STA-1E • Re-evaluate proposed remedy (EAARFS): • Increasing trends in S5A TP Concs (200-250 ppb vs. EAARFS assumed 160 ppb) • Predicted pulsed inflows to STA-1W - risk of bypass & P spikes to marsh. • Plans will not meet QBEL (max yearly < 17 ppb) required to restore exterior marsh • Risk to Refuge water supply . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage . Topographic map of the Refuge marsh (figure provided by Dr. E.A. Meselhe based on USGS topography data). Elevations are in feet, NGVD29.Form USGS data; Southern End – Lower Elevation – More Susceptible to Intrusion at a given Rim canal stage

More Related